Problem: Stephanie eats at a cafe and the cost of her meal is $\$38.00$. She would like to leave a $15\%$ tip. What is her total bill including tip?
Answer: The tip amount is equal to $15\% \times \$38.00$ We can find the tip by first calculating a $10\%$ tip and a $5\%$ tip, and then adding those two numbers together. To calculate a $10\%$ tip, move the decimal point in $\$38.00$ one place to the left. $10\%$ $\times \$38.00$ $\$3.80$ To calculate a $5\%$ tip, divide the $10\%$ tip amount in half. $5\%$ $\times \$38.00 = $ $\$3.80$ $ \div 2 = $ $\$1.90$ Adding the two amounts together gives us $\$3.80$ $\$1.90 =$ $ \$5.70$ The cost of the meal plus the amount of the tip will equal the total bill amount. $\$38.00 + \$5.70 = $ $\$43.70$ The total cost of the bill is $\$43.70$.